One vertex per element, one color per generator, with an edge from x to x·s.
(5,6)(7,14)(8,11)(9,13)(10,15)(12,18)(16,20)(17,19)(21,22,26,34,25,29,24,28)(23,30,31,27,33,35,32,36)(1,2)(3,4)(5,7,9,16)(6,10,13,19)(8,17,18,15)(11,14,12,20)(2,4)(21,23)(22,27)(24,31)(25,33)(26,32)(28,35)(29,36)(30,34) involution — undirected(6,11)(8,18)(10,14)(12,13)(15,17)(19,20)(21,24,25,26)(22,28,29,34)(23,31,33,32)(27,35,36,30)A Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.